PRECISION PLIERS

Abstract: Pliers comprising two shanks connected at a joint, where the shanks behind the joint being shaped as handles with covers of polymeric material, the outsides (18, 19) of the covers in a front portion (14, 15) forming when the handles are squeezed together a major part of a rotational, preferably cylindrical or conical surface with smaller span than the rear portion (16, 17) of the handles.

Description: PRECISION PLIERS Background Various types of pliers are used to hold and orient small items, especially during assembly and service of instruments, electronics and precision mechanics, also in surgery and cosmetic treatments. The invention concerns a new configuration of the handles of the pliers to make it possible to handle and orient small items with higher precision than with previously known pliers. Description The invention is described with reference to the figures, where figure 1 shows a side view of a pliers according to the invention, and figure 2 shows in a front view how the pliers is held in the hand during high precision work. A pliers according to the invention is shown in figure 1 and comprises two shanks hingedly connected at a joint (13) . In front of the joint the shanks are shaped as jaws (11,12) and behind the hinge as handles with covers of soft polymer material. The jaws (11,12) may be different according to their use, round, flat, curved or sharp edged. The handles consist of two portions, a rear portion (16,17) to be gripped by the palm of the hand, and a front portion (14,15) to be gripped with the thumb and index fingers. Within the rear portion (16,17) the handles are curved to have a convex outer contour, and to let the widest span for a closed pliers, measured on the outside of the handles, be close to the center of the rear portion, not at the rear end (20,21) of it. The front portion (14,15) is so shaped that when the pliers CONFIRMATION PY is closed the outsides (18,19) of the handle covers together form at least half of a rotational surface, preferably cylindrical or conical, which can be gripped with the thumb and index finger as shown in figure 2. The span measured on the outsides shall be smaller in the front portion then in the rear portion. In a cross-section through the front portion the outsides (18,19) will each form a circular arc of at least 90 degrees, preferably 120 degrees, and when the pliers is closed by squeezing the handles, the arcs will have substantially the same center, making the span in this section substantially equal to the diameter of the arcs. The effect of this is that the pliers can be easily twirled between the thumb and the index finger to orient the shanks and any item held between the jaws in any desired angular position. The force between the thumb and the index finger will not cause any resulting torque on the pliers or the item. A corresponding motion with a pliers according to prior art where the handle covers do not form any cylindrical or conical front portion (14,15) will require either changing the grip of the palm, or performing the motion by rotating he whole hand, neither of which can be done with high precision. Compared to prior art, a pliers according to the invention will have handle covers with great lateral width, at least 70 % of the gripping span in the front portion when the pliers is closed. A pliers according to the invention can be combined with return springs or locking means of known types.

Claims: CLAIMS 1. Pliers comprising two shanks hingedly connected at a joint (13) , with the shanks behind the joint shaped as handles with covers of polymeric material and in a .rear portion having a convex outer contour, characterized by the outsides (18,19) of the handle covers in a front portion (14,15) forming part of a rotational surface when the pliers is closed by squeezing the handles. 2. Pliers according to claim 1, characterized by the rotational surface being cylindrical or conical. 3. Pliers according to claim 1, characterized by the outsides (18,19) of the covers in a cross-section through the front portion being circular arcs, each at least 90 degrees. 4. Pliers according to claim 1, characterized by the lateral width of the handle covers in a front portion (14,15) being larger than 70 % of the span between the outside contours in the same portion when the shanks are squeezed together.

Inventors: BERGQVIST HAAKAN, BOBJER OLLE, HIMBERT HANS, JANSSON CONNY, BERGQVIST, HAAKAN, BOBJER, OLLE, HIMBERT, HANS, JANSSON, CONNY
Applicants: BERGQVIST HAAKAN, BOBJER OLLE, HIMBERT HANS, JANSSON CONNY, SANDVIK AB, BERGQVIST, HAAKAN, BOBJER, OLLE, HIMBERT, HANS, JANSSON, CONNY
Application year: 1994
Main classification: B25B7
IPC codes: B25B7, B25G1